Downhole tubular expander and method

Abstract

A liner hanger ( 10 ) is provided for supporting a liner in a well. An expandable tubular hanger ( 90 ) is positioned within the well and a running tool with a tool mandrel ( 34 ) passes fluid through the running tool. An actuator ( 12 ) forcibly moves the tubular expander to an expanded position. Release of the running tool from the liner may be accomplished with a retainer ( 84 ) and downward movement of the mandrel, with fluid pressure acting on a hydraulic piston ( 28 ) coupled with rotation of the mandrel, or by safety joint ( 68 ) along the tubular mandrel.

1. A liner hanger for supporting a liner in a well, comprising:
 an expandable tubular hanger having initial run-in diameter and an expanded diameter for supporting the liner in the well; 
 a running tool supported on a work string and having an internal bore within a tool mandrel for passing fluid through the running tool; 
 a tubular expander supported on the running tool, the tubular expander having an expander outermost diameter greater than the initial run-in diameter of the tubular hanger; 
 an actuator for forcibly moving the tubular expander axially from a position substantially axially spaced from the tubular hanger to a position substantially within the tubular hanger, thereby radially expanding the tubular hanger; 
 a retainer secured to the tool mandrel, such that downward movement of the work string and the retainer releases collet fingers connecting the tool mandrel to the tubular hanger, thereby releasing the collet fingers from the tubular hanger so that the tool may be retrieved to the surface by a first release mechanism; 
 a hydraulic piston responsive to fluid pressure within the mandrel to selectively engage and disengage a clutch rotatably interconnecting the tool mandrel and a housing supporting latching members, the latching members rotatably interconnecting the tubular hanger and the housing, such that when the clutch is disengaged, rotation of the mandrel will unthread the retainer from the tubular hanger, thereby providing a second release mechanism to retrieve the tool to the surface; and 
 a safety joint threadably connecting the tool mandrel and the upper collet retainer, such that left-hand rotation of the mandrel axially lowers the retainer relative to the collet fingers, thereby providing a third release mechanism to retrieve a substantial portion of the tool to the surface. 
 
     
     
       2. A liner hanger as defined in  claim 1 , wherein rotation of a work string and the mandrel to the right rotates the liner to the right when the clutch is engaged, and rotation of the mandrel to the right unthreads the retainer when the clutch is disengaged. 
     
     
       3. A liner hanger as defined in  claim 1 , wherein the tubular expander remains downhole with the expanded tubular hanger to support the liner in the well. 
     
     
       4. A liner hanger as defined in  claim 1 , wherein the actuator comprises a plurality of axially stacked pistons powered by fluid pressure within the mandrel. 
     
     
       5. A liner hanger as defined in  claim 1 , wherein the safety joint is provided above the retainer. 
     
     
       6. A liner hanger as defined in  claim 1 , wherein the clutch is provided below the retainer. 
     
     
       7. A liner hanger as defined in  claim 1 , wherein the latching members are outwardly biased. 
     
     
       8. A liner hanger as defined in  claim 1 , wherein the liner supports a bit at a lower end thereof. 
     
     
       9. A liner hanger for supporting a liner in a well, comprising:
 an expandable tubular hanger having initial run-in diameter and an expanded diameter for supporting the liner in the well; 
 a running tool supported on a work string and having an internal bore within a tool mandrel for passing fluid through the running tool; 
 a tubular expander supported on the running tool, the tubular expander having an expander outermost diameter greater than the initial run-in diameter of the tubular hanger; 
 an actuator for forcibly moving the tubular expander axially from a position substantially axially spaced from the tubular hanger to a position substantially within the tubular hanger, thereby radially expanding the tubular hanger; 
 a retainer secured to the tool mandrel, such that downward movement of the work string and the retainer releases the tool mandrel from the tubular hanger so that the tool may be retrieved to the surface by a first release mechanism; 
 a hydraulic piston responsive to fluid pressure within the mandrel to selectively engage and disengage a clutch rotatably interconnecting the tool mandrel and a housing supporting latching members, the latching members rotatably interconnecting the tubular hanger and the housing, such that when the clutch is disengaged, rotation of the mandrel will unthread the mandrel from the tubular hanger, thereby providing a second release mechanism to retrieve the tool to the surface; and 
 a safety joint threadably connecting the tool mandrel and the tubular hanger, such that left-hand rotation of the mandrel axially lowers the retainer relative to the collet fingers, thereby providing a third release mechanism to retrieve the tool to the surface. 
 
     
     
       10. A liner hanger as defined in  claim 9 , wherein rotation of the work string and the mandrel to the right rotates the liner to the right when the clutch is engaged, and rotation of the mandrel to the right unthreads the retainer when the clutch is disengaged. 
     
     
       11. A liner hanger as defined in  claim 9 , wherein the liner supports a bit at a lower end thereof. 
     
     
       12. A liner hanger as defined in  claim 9 , wherein the latching members are outwardly biased. 
     
     
       13. A liner hanger as defined in  claim 9 , wherein the tubular expander remains downhole with the expanded tubular hanger to support the liner in the well. 
     
     
       14. A liner hanger as defined in  claim 9 , wherein the actuator comprises a plurality of axially stacked pistons powered by fluid pressure within the mandrel. 
     
     
       15. A liner hanger for supporting a liner in a well, comprising:
 an expandable tubular hanger having initial run-in diameter and an expanded diameter for supporting the liner in the well; 
 a running tool supported on a work string and having an internal bore within a tool mandrel for passing fluid through the running tool; 
 a tubular expander supported on the running tool, the tubular expander having an expander outermost diameter greater than the initial run-in diameter of the tubular hanger, the tubular hanger remaining downhole with the expanded tubular hanger to support the liner in the well; 
 an actuator including a plurality of axially stacked pistons for forcibly moving the tubular expander axially from a position substantially axially spaced from the tubular hanger to a position substantially within the tubular hanger, thereby radially expanding the tubular hanger; 
 a retainer secured to the tool mandrel, such that downward movement of the work string and the retainer releases collet fingers connecting the tool mandrel to the tubular hanger, thereby releasing the collet fingers from the tubular hanger so that the tool may be retrieved to the surface by a first release mechanism; 
 a hydraulic piston responsive to fluid pressure within the mandrel to selectively engage and disengage a clutch rotatably interconnecting the tool mandrel and a housing supporting latching members, the latching members rotatably interconnecting the tubular hanger and the housing, such that when the clutch is disengaged, rotation of the mandrel will unthread the retainer from the tubular hanger, thereby providing a second release mechanism to retrieve the tool to the surface; and 
 a safety joint threadably connecting the tool mandrel and the upper collet retainer, such that left-hand rotation of the mandrel axially moves the retainer relative to the collet fingers, thereby providing a third release mechanism to retrieve the tool to the surface. 
 
     
     
       16. A liner hanger as defined in  claim 15 , wherein rotation of the work string and the mandrel to the right rotates the liner to the right when the clutch is engaged, and rotates the mandrel to the right and unthreads the retainer when the clutch is disengaged. 
     
     
       17. A liner hanger as defined in  claim 16 , wherein the liner supports a bit at the lower end thereof. 
     
     
       18. A liner hanger as defined in  claim 15 , wherein the third release mechanism is provided above the first release mechanism. 
     
     
       19. A liner hanger as defined in  claim 15 , wherein the clutch is provided below the first release mechanism. 
     
     
       20. A liner hanger as defined in  claim 15 , wherein the latching members are outwardly biased.